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A physicist argues that information is at the root of everything

economist.com

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Re: A physicist argues that information is at the root of everything

#31

Post by jessriedel »

hga wrote: post #6

From the most useful Amazon.com review of the book ( http://www.amazon.com/review/R15E7HO19A2FQF/ref=cm_cr_rdp_pe... ): " The core of the argument (on page 201) I will not spoil here, but it's not wholly convincing on several grounds. First, although he does not further dwell on it, the author favors the 'Copenhagen' (or observer effect) interpretation of quantum physics, which is used to buttress & underpin his argu…

It's not so much that MWI is all that satisfying, it's that Copenhagen is incoherent.

Re: A physicist argues that information is at the root of everything

#32

Post by ovi256 »

hga wrote: post #28
goodside wrote: post #26

Earlier quoted context omitted.

Whether a physicist (in modern times and below a certain age) espouses MWI is quickly becoming a great litmus test for whether you should bother listening to them on anything that isn't established textbook material. Copenhagen is pseudo-scientific nonsense, and I'm amazed anyone can work on developing quantum computers while simultaneously denying the existence of what they're designing. I'd cut him some slack if th…

" Whether a physicist (in modern times and below a certain age) espouses MWI is quickly becoming a great litmus test for whether you should bother listening to them on anything that isn't established textbook material. " Errr, do you mean you should bother listening or not bother? My understanding of MWI doesn't go much beyond what I could understand of an early Wheeler paper (I thought it was from the mid-40s, but W…

  My understanding of MWI doesn't go much beyond what I could understand of an early Wheeler paper (I thought it was from the mid-40s, but Wikipedia says MWI starts with the thesis of a student of his with the first publication in 1957 ... and I read that paper (whenever it was published) 25 years ago so it's gotten pretty fuzzy).
Well, in this universe it started in '57. In yours, it seems, it is different. Where are you from traveller ?

Re: A physicist argues that information is at the root of everything

#33

Post by davidmathers »

hga wrote: post #6

From the most useful Amazon.com review of the book ( http://www.amazon.com/review/R15E7HO19A2FQF/ref=cm_cr_rdp_pe... ): " The core of the argument (on page 201) I will not spoil here, but it's not wholly convincing on several grounds. First, although he does not further dwell on it, the author favors the 'Copenhagen' (or observer effect) interpretation of quantum physics, which is used to buttress & underpin his argu…

On the other hand MWI super-advocate David Deutsch says: "An engaging, non-technical exploration of what the new theory of quantum information and computation tells us about life, the universe, and everything."

Re: A physicist argues that information is at the root of everything

#34

Post by Carcarius »

I know nothing, but here are my thoughts...

What is information really? Does information exist without a conscious being to interpret it? Are the laws that govern information simply laws that are created by conscious beings for the purpose of interpreting the information? Most laws that we are concerned with are derived from nature, through our senses and experience of cause and effect. Our senses allow us to perceive the changes in state of our surrounding environment. These changes in state is information.

I guess the point I am finally making, is that the statement above concerning information is expected in lieu of our current focus, reliance, and addiction on information as a representation of reality. I am not sure what the difference is between the laws that govern matter and the laws that govern information. We're still working with information in either case. We have to take measurements, interpret the data, make predictions, and build systems to exploit the "laws" we've uncovered.

Re: A physicist argues that information is at the root of everything

#35

Post by danbmil99 »

It seems quite strange if, as alleged 3rd hand in this thread, Vedral is obsessed with quantum computing, but sticks with the antiquated and more or less content-free Copenhagen interpretation. MWI seems to me to be critical to quantum computing -- otherwise, where is all that extra computing power coming from?

Re: A physicist argues that information is at the root of everything

#36

Post by phaedrus »

Carcarius wrote: post #34

I know nothing, but here are my thoughts... What is information really? Does information exist without a conscious being to interpret it? Are the laws that govern information simply laws that are created by conscious beings for the purpose of interpreting the information? Most laws that we are concerned with are derived from nature, through our senses and experience of cause and effect. Our senses allow us to perceiv…

I think you're substituting some colloquial fuzzy/subjective definition of the word "information" here as "a conscious being knowing something." But in the context of the linked article, we're talking about Information in the context of Information Theory. It is not subjective. The remarkable thing about Shannon's information theory is that he does formulate real laws of information on the same solid, objective footing as laws of physics.

But then, I could have stopped reading at your first line: it sums up your entire post.

Re: A physicist argues that information is at the root of everything

#37

Post by gintas »

I did my Masters thesis informational ontology. Here's the thing: Shannon's information theory is a mathematical formalism, and is not enough to define information. Furthermore, information can only be defined within bounds of a model, and there are typically many ways and many abstraction levels available to describe a phenomenon, so the question of objectivity of information is still open.

If to assert objectivity you try to pick the lowest possible layer of abstraction at the quantum mechanics level, you lose the whole layer of semantic information, i.e. information about something, which is actually the primary concept of information, and "information" simply becomes a name for a set of mathematical formulas, and as such it may not be treated as a substance.

Re: A physicist argues that information is at the root of everything

#38

Post by ars »

danbmil99 wrote: post #35

It seems quite strange if, as alleged 3rd hand in this thread, Vedral is obsessed with quantum computing, but sticks with the antiquated and more or less content-free Copenhagen interpretation. MWI seems to me to be critical to quantum computing -- otherwise, where is all that extra computing power coming from?

That doesn't make as much sense as it sounds like it does.

From a macro point of view the multiple worlds are all identical. All. The business with hitler doing something different in a different world is nonsense, quantum uncertainty almost never has any effect in the macro world.

So when you are computing in your world, everyone is doing the same computation in all the worlds.

Part of the MWI is that each world has a slightly different version of the event, and you just see yours, which was effected by theirs. But in a quantum computer you specifically set it up so that your get a single right answer - but if you get just one answer, all the worlds are the same, so how do you get multiple worlds each working on it?

Re: A physicist argues that information is at the root of everything

#39

Post by khafra »

Daniel_Newby wrote: post #25
Confusion wrote: post #13

Mistaking the deepest abstraction you are capable of for the fundament of all reality is hubris. Philosophy is one of those subjects that most intelligent persons think they can master pretty well. It all seems pretty simple and straightforward. Especially physicists fall into that trap again and again, up to great string theorists putting forward anthropocentric theories of the universe. These people usually make tr…

"He defines information based on the frequency of 'events'. This means that both time and 'events' are more primal than his notion of 'information'." True, but what do you expect for a popular review of a book that itself is a popular review of some pretty abstract ideas. The basic concept is not just that our universe can be described by statistical measures, but that the foundational laws seem to be governed by sta…

Well put. The one alteration I'd make is that universes of pure thought would require a Tegmark Level IV type multiverse, not just a MWI or black-hole-spawning type multiverse.

Re: A physicist argues that information is at the root of everything

#40

Post by goodside »

jessriedel wrote: post #30
goodside wrote: post #26

Earlier quoted context omitted.

Whether a physicist (in modern times and below a certain age) espouses MWI is quickly becoming a great litmus test for whether you should bother listening to them on anything that isn't established textbook material. Copenhagen is pseudo-scientific nonsense, and I'm amazed anyone can work on developing quantum computers while simultaneously denying the existence of what they're designing. I'd cut him some slack if th…

The reason people can get away with Copenhagen is that decoherence is absurdly effective in all realistic cases, causing there to very little uncertainty about whether and when a measurement happened. Insofar as we can all agree when a measurement happened, physicists operating under Copenhagen are going to be just as effective as those who understand MWI. And for most of the theoretical and especially computational…

"Insofar as we can all agree when a measurement happened, physicists operating under Copenhagen are going to be just as effective as those who understand MWI."

Agreed. If you're only worrying about the mundane medium-sized world we live in and what QM predicts we'll see in it, MWI vs. Copenhagen won't matter. Here, it does, as he's apparently using Cop. as a part of his argument.

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